#include <bits/stdc++.h>
using namespace std;

bool cmp(pair<double, double> p1, pair<double, double> p2)
{
    if (p1.first != p2.first)
        return p1.first < p2.first;
    else
        return p1.second < p2.second;
}

int main()
{
    vector<pair<double, double> > res;
    for (int x1 = 0; x1 < 20; x1++)
        for (int y1 = 0; y1 < 21; y1++)
            for (int x2 = 0; x2 < 20; x2++)
                for (int y2 = 0; y2 < 21; y2++)
                    if (x1 != x2)
                    {
                        double k = (double)(y2 - y1) / (x2 - x1);
                        double b = y1 - k * x1;
                        pair<double, double> p(k, b);
                        res.push_back(p);
                    }
    sort(res.begin(), res.end(), cmp);
    int ans = 1;
    for (int i = 1; i < res.size(); i++)
        if (fabs(res[i].first - res[i - 1].first) > 1e-8 || fabs(res[i].second - res[i - 1].second) > 1e-8)
            ans++;

    cout << ans + 20 << endl;
    return 0;
}